The French Football Federation (FFF) announced that the Real Madrid man has to rest for an 'indefinite period' in order to reach full recovery.

"Medical tests have revealed an unforeseeable illness which justifies a rest period," Les Bleus spokesman Francois Manardo stated.

"As a consequence, Lassana Diarra will miss the World Cup."

Diarra was part of France's 24-man squad.

France squad:

Goalkeepers: Hugo Lloris (Olympique Lyon), Steve Mandanda(Olympique Marseille), Cedric Carrasso (Girondins Bordeaux)

Defenders: Bacary Sagna (Arsenal), Patrice Evra (Manchester United), William Gallas (Arsenal), Eric Abidal (Barcelona), Sebastien Squillaci (Sevilla), Marc Planus (Girondins Bordeaux), Gael Clichy(Arsenal), Anthony Reveillere (Olympique Lyon).

Midfielders: Alou Diarra(Girondins Bordeaux), Jeremy Toulalan (Olympique Lyon), Florent Malouda (Chelsea), Yoann Gourcuff (Girondins Bordeaux), Abou Diaby (Arsenal), Franck Ribery (Bayern Munich).

Forwards: Thierry Henry (Barcelona), Nicolas Anelka (Chelsea), Andre-Pierre Gignac (Toulouse), Sidney Govou (Olympique Lyon), Djibril Cisse (Panathinaikos), Mathieu Valbuena (Olympique Marseille).